Jellies in the Water

I was surfing clean Kelley's Cove this week. Tuesday maybe? At first I thought I saw a jelly in the water. But then I was like, no way. Then I thought I saw two jellies! So I paddled over and it was just a leaf. But then moments later I saw a jelly for real. It was about the size of a soccer ball, red, ugly, and gelatinous. I saw about 6 during my session. Anyone got any info on these suckers?